Method of forming a flared-end pipe with a reduced resistance bead seal and method of use

ABSTRACT

A reduced resistance bead seal is integrally formed on a mounting surface of two matingly engageable members to form a leak-free seal between the two members despite any eccentricity or angular variances between the two members. In one embodiment, the reduced resistance bead is formed on an inner conical flange of an inverted flared end of a hollow fluid conduit. The bead presents a deformable surface as a fitting urges the flared end of the conduit into engagement with a conical seat in a receiver where eccentricity or angular variances exist between the flared end of the conduit and the conical seat. A unique method and a unique forming tool are used to form the reduced resistance bead in the flared end of the conduit simultaneously with the flaring of the end of the conduit.

This application is a CONTINUATION of application Ser. No. 08/441,663,filed on May 15, 1995, now abandoned, which is a division of applicationSer. No. 08/111,980) filed Aug. 25, 1993, now U.S. Pat. No. 5,489,127issued Feb. 6, 1996.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates, in general, to fluid conduits and, morespecifically, to fluid conduit mounting apparatus.

2. Description of the Art

It is well known to flare the end of a fluid conduit to enable the endof the conduit to be easily attached to a suitable element, such as avalve, receiver, fitting, etc. In high pressure fluid conduits employedin vehicle brake and fluid lines, SAE standards require a double orinverted flared end on such conduits. In a double or inverted flaredconduit, the end of the conduit is flared radially outward from theaxial extent of the conduit and then an outer portion of the end is bentinward in parallel to and in registry with an outer surface of theflared end of the conduit to form a double flared wall at the end of theconduit with inner and exterior conical surfaces.

In a typical mounting arrangement, the double or inverted flared end ofthe conduit sealingly mates with a conically shaped seat in a femalefitting, commonly referred to as a receiver. A bore in the receiveraligns with the bore in the conduit to form a fluid flow paththerethrough. A male fitting is threadingly engaged with the receiverand also includes an internal conical surface which engages the exteriorconical surface of the flared end of the conduit to urge the inner,folded over conically shaped flange of the flared end of the conduitinto mating engagement with the conical seat in the receiver.

In the past, the fittings were made on lathes with rotating spindlessuch that the threads and the seal face or surface were machined on thesame spindle. This method of processing produced concentric flare coneand thread center lines. However, current practice utilizes a moreeconomical cold headed process for making the fittings and theseparately processed rolled threads do not deliver the same high degreeof concentricity as the more costly screw machine method.

The proper operation of such a fluid conduit fitting requires that theflared end of the conduit completely seat on the mating conical seat ofthe receiver about its full 360° surface. This is not always possibledue to the aforementioned use of the cold headed process which does notdeliver the same high degree of concentricity as the screw machinemethod of forming such fittings and receivers. Further, traditionalmanufacturing tolerance of TIR (total indicated runout) can result in aneccentric alignment of the flared end of the conduit and the matingconical seat of the receiver, despite such parts being within theirspecified manufacturing tolerances. A large TIR can create a gapextending along a predetermined angular extent of the adjacent conicalsurfaces of the conduit and the receiver which causes leaks in the fluidsystem.

In the past, when a leak occurred, it was common to apply more torque tothe fitting to forcibly urge the fitting and thereby the entire conicalsurface of the flared end of the conduit into engagement with theconical seat of the receiver. However, such additional torque is notalways able to be easily applied to the fitting. In the past, sealingwas obtained by utilizing a soft material for either the conduit or theinternal flare seat in the receiver. Typically, the conical flare seatin the receiver was made of brass or, in later years, a brass seatinsert was mounted in a steel receiver body. The softer brass materialof the conical flare seat deformed under increased torque applied to thefitting to enable the flared end of the conduit to be forced into matingcontact with the conical seat over the full 360° extent of the conicalseat despite any eccentricity which may exist between the flared end ofthe conduit, the conical seat or the axial alignment of the conduit withthe conical seat in the receiver.

Newer receivers are formed primarily of steel, cast iron or anodizedaluminum which are harder than brass and not as forgiving. Suchreceivers require higher torque to deform the flared end of the conduitinto complete mating engagement with the conical seat of the receiver toform a leakproof annular seal between the mating surfaces thereof. Suchincreased torque is not always possible or desirable.

Thus, it would be desirable to provide a mounting arrangement for twomating elements which includes a reduced resistance bead on the matingsurface of one of the elements to form a leakproof seal when the twoelements are brought together into forced engagement. It would also bedesirable to provide a unique flared end on a high pressure fluidconduit which creates a leak free seal with a mating surface or seatwithout the use of additional seal elements, increased tighteningtorque, special tools or modifications to the mating fitting elements.It would also be desirable to provide a flared end conduit having uniquemeans for forming a leakproof seal with a mating surface of anotherelement, which means is integral with the conduit so as to always bepresent with the conduit, which eliminates any additional manufacturingoperations required to assemble the seal, and which is formed of thesame material as the conduit. It would also be desirable to provide aseal on the flared end of a fluid conduit which is deformed under normalor even reduced torque to account for eccentricity and angular variancesbetween the mating surfaces of the fitting and the conduit end. Finally,it would be desirable to provide a mounting apparatus, method and toolwhich provides a unique seal element on the flared end of a fluidconduit for forming a leakproof seal with a mating element which ismanufacturable using conventional methods and techniques.

SUMMARY OF THE INVENTION

The present invention is a mounting apparatus having a unique sealelement for forming a leakproof seal between the mating mountingsurfaces of two joined members despite any eccentricity, angularvariances or misalignment of the two joined members.

In one embodiment, first and second members have first and secondmatingly engageable mounting surfaces, respectively. A reducedresistance bead, preferably an annular bead, is integrally formed withone of the members as a continuous one-piece part of the member andextends outward from the mounting surface of the member to form adeformable seal between the two members when the two members areforcibly joined together. The reduced resistance bead may take one of anumber of different shapes, including an arcuate shape, i.e., sphericalor elliptical, as well as various polygonal shapes, such as generallyrectangular, trapezoidal, etc.

In a more specific application, the first member has a first endextending at a predetermined angle from the axial extent of the firstmember. A first mounting surface is formed on the first end of the firstmember for mating engagement with the mounting surface of the secondmember. The reduced resistance bead is formed on the mounting surface ofthe first member. In this application, the first member may comprise afluid conduit in which the first end flares radially outward in a singleflange from the axial extent of the conduit, at a predetermined angle,such as 45°. The first end of the conduit may also be formed as a doubleor inverted flared end with an outer conical flange and an inner conicalflange formed as a continuous extension of the outer flange and disposedradially inwardly of and in registry with the outer flange. The reducedresistance bead is formed on and extends outward from the inner flange.

The present invention also comprises a fluid conduit connector apparatuswhich includes a fluid conduit having a first end flared radiallyoutward from the diameter of the conduit to an enlarged diameter. Theflared end of the conduit has a first exterior flange with a firstconical exterior surface formed thereon. In a double or inverted flareconduit a portion of the flared end of the conduit is bent inwardly fromthe first exterior flange into registry with the first flange to form aninner flange having a second conical surface thereon disposedsubstantially parallel to the first conical surface of the firstexterior flange. A seal element in the form of a reduced resistance beadis integrally formed as a continuous part of the inner flange andextends outward from the second conical surface of the inner flange. Afirst fitting having a through bore for receiving the fluid conduittherethrough has a conical surface engageable with the first conicalsurface on the flared end of the conduit. In a single flared endconduit, the bead is formed on the inner or second conical surface ofthe single end flange. A receiver means has a conical seat for matinglyreceiving the second conical surface of the fluid conduit thereon. Meansare provided for forcibly attaching the fitting to the receiver means tothereby force the conical surface of the fitting into engagement withthe first exterior conical surface of the conduit and the second conicalsurface of the conduit into engagement with the conical seat of thereceiver means.

If any eccentricity or angular variances exist in the first and secondconical surfaces of the conduit, the conical surface of the fitting, orthe conical seat of the receiver means when such elements are engagedwith each other, the softer of the conical seat or the reducedresistance bead on the conduit will deform to enable the second or innerconical surface of the conduit to completely seal over its full 360°annular extent with the conical seat of the receiver means.

Also disclosed in the present invention is a method of forming a sealelement on a flared end on a fluid conduit. The method comprises thesteps of:

a) flaring the first end of a hollow fluid conduit radially outward fromthe axial extent of the conduit;

b) bending a portion of the first end of the conduit inward on itself toform exterior and inner substantially parallel conical surfaces on thefirst end of the conduit; and

c) forming a reduced resistance bead on the inner conical surface of theconduit extending outward from the inner conical surface.

Preferably, the step of forming the reduced resistance bead is performedsimultaneously with the step of bending the first end of the conduitinward on itself.

This method may be modified by eliminating step (b) for a single flaredend conduit and forming the bead on the inner surface of the singleflared end of the conduit.

The present invention also describes a method of forming a reducedresistance section on any component. According to this method, first andsecond members are formed with first and second mounting surfaces,respectively. A reduced resistance bead is formed on the mountingsurface of one of the members and extends outward from the mountingsurface for engagement with the corresponding mounting surface of theother member when the two members are forcibly engaged.

Also disclosed is a unique tool for forming a reduced resistance bead ina hollow fluid conduit having a flared end with folded over,substantially parallel, inner and outer flanges. The tool includes ashank having a conical surface formed at one end. A recess is formed inthe conical surface having a predetermined shaped cross section to forma reduced resistance annular bead when the tool is forcibly urged intothe flared end of the fluid conduit. A piloting nose is mounted at theend of the conical surface.

The present invention provides a unique mounting apparatus whichprovides a leak free seal between the mating surfaces of two elementsdespite any eccentricity, angular variances, or misalignment of the twoelements. Such leak resistance or leak free sealing is provided atnormal and even reduced joint loading torques or forces. The use of anannular reduced resistance bead formed on the mounting surface of oneelement also provides a longer leak path for increased leak resistance.

The mounting apparatus of the present invention is particularly usefulon the flared ends of fluid conduits which are sealingly attached toreceivers by means of fittings. The present invention provides a leakfree seal between the mating surfaces of the flared end of the conduitand a conical seat in the receiver even if eccentricity or angularvariances exist between the conical mating surfaces of the conduit andthe conical seat of the receiver.

The reduced resistance section or bead provides improved sealing andleak resistance without the use of increased loading forces on thefitting which necessitate metal deformation of the fitting and/orspecial tooling or the use of separate seal members, all adding to thecost of the fitting assembly. The reduced resistance bead is integrallyformed with the conduit so as to always be present with the conduit soas to eliminate any separate assembly steps for attaching a seal elementto the conduit. Further, the reduced resistance bead is integrallyformed with the conduit so as to be constructed of the same material asthe conduit thereby eliminating any design or use considerationsrelating to different deterioration rates of disparate materials.

A conduit or member having the reduced resistance bead of the presentinvention formed thereon is usable as a direct, drop-in replacement forsimilar conduits or members without modification to the fitting,receivers or assembly methods associated with such components.

Finally, the reduced resistance annular bead is angular tolerant in thatit seats in a centered mounting arrangement or a conical seat or surfacedespite any eccentricity or angular variances between the conduit andthe mating seat or surface.

BRIEF DESCRIPTION OF THE DRAWING

The various features, advantages and other uses of the present inventionwill become more apparent by referring to the following detaileddescription and drawing in which:

FIG. 1 is a cross sectional view of a fluid conduit having a reducedresistance bead of the present invention formed on the flared endthereof;

FIG. 2 is a plan view showing the first step in a method of forming theflared end of a conduit with a reduced resistance bead shown;

FIG. 3 is a plan view of a second step in the method of the presentinvention showing the formation of the reduced resistance bead on theinverted flared flange end of the conduit formed in FIG. 2;

FIG. 4 is an enlarged view of a unique tool used to form the reducedresistance bead in the inverted flange of the conduit shown in FIG. 3;

FIG. 5 is a cross sectional view showing the assembly of the conduitshown in FIG. 1 with a fitting and receiver;

FIG. 6 is a partial, enlarged view, similar to FIG. 5, but showing adifferent sealing arrangement of the reduced resistance bead on theconical seat of the receiver;

FIG. 7 is an elevational view showing the use of a reduced resistancebead of the present invention with two mating members;

FIG. 8 is a partial, enlarged view, showing an alternate configurationof the reduced resistance bead shown in FIG. 1;

FIG. 9 is a partial, enlarged view showing a reduced resistance bead ofthe present invention on a single flared end conduit; and

FIG. 10 is a cross sectional view showing the conduit depicted in FIG. 9mounted in a two piece tube assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is directed to the formation of a seal between themating surfaces of two elements which creates a leak free seal despiteany eccentricity, angular variance, or misalignment between the matingsurfaces of the two elements.

Referring now to FIG. 1, there is depicted one example of the use of thepresent invention on the flared end of a fluid conduit 10. It will beunderstood, as described in greater detail hereafter, that the presentinvention may also be employed with other types and shaped elements.

The fluid conduit 10 is typical of a conduit design to carry fluid, suchas air, hydraulic fluid, etc., under pressure. The conduit 10 typicallyhas a circular cross section with an internal bore 13 formed by a sidewall 12. The conduit 10 may have any thickness side wall 12, I.D. andO.D. Further, the conduit 10 may be formed by any metallic material,such as steel, aluminum, copper, etc.

As is conventional, the conduit 10 has a first end 14 having an openingtherein which communicates with the internal bore 13 of the conduit 10.The first end 14 is flared radially outward at a predetermined angle toenable the first end 14 of the conduit 10 to be sealingly mounted toanother member, such as a receiver in an example described in greaterdetail hereafter.

According to SAE standards for the use of high pressure fluid conduitsin vehicle brake lines, fuel lines, etc., the first end 14 of theconduit 10 is flared outward from the axial extent of the conduit 10 ata 45° angle. It will be understood that any other angle may be employedwith the present invention, including flared end angles greater than 0°and up to 90° or more.

As shown in FIG. 1 for one embodiment of the present invention, thefirst end 14 of the conduit 10 has a double or inverted flared endconstruction formed of an exterior flange 16 having an exteriorconical-shaped surface 18. A portion of the first end 14 is folded orbent inward onto itself to form an inner flange 20 which is disposed inregistry with and parallel to the exterior flange 16. The inner flange20 forms an inner conical surface 22 which is desirably parallel to theexterior surface 18 of the exterior flange 16. The inner conical surface22 is designed to sealingly mate with a correspondingly formed conicalseat on a mating element, such as a receiver in metal-to-metal contact.

Ideally, the inner and outer surfaces 22 and 18, respectively, on theconduit 10 are arranged in parallel and concentric to each other and tothe axial center line of the conduit 10. However, due to manufacturingtolerances, manufacturing variations, and variations in the materialused to form the conduit 10, eccentricity or angular variances betweenthese surfaces and with the mating, conical seat may exist. The presentinvention uniquely provides a compressive bead seal or bead 28 having areduced resistance which is integrally formed as a unitary part of theinner flange 20. The bead 28 extends outward from the inner flange 20 asshown in FIG. 1. Further, the bead 28 may have any one of a number ofdifferent shapes or cross sections. For example, the bead 28 may have anarcuate shape, such as the illustrated spherical shape or an ellipticalshape. Alternately, as shown in FIG. 8, the bead 28 may have a generallypolygonal shape, such as a trapezoidal, triangular, rectangular,rhombic, etc., denoted by reference number 29 with flat sides. Inaddition, although one annular bead 28 is shown in FIG. 1, multiplebeads having the same or different cross section shapes, as describedabove, may also be formed on the inner flange 20 of the conduit 10.

The reduced resistance bead 28 provides a smaller volume of materialthan that of the entire inner flange 28 of the conduit 10 so as to beeasily deformable itself or to easily deform a softer mating element toconform the first end 14 of the conduit 10 to a mating element to form aleak free seal therebetween.

FIGS. 2, 3 and 4 depict a method and an unique tool used to form thereduced resistance bead 28 as well as to flare the first end 14 of theconduit 10 to the shape shown in FIG. 1.

In FIG. 2, one of a pair of holding blocks 30 is depicted. The holdingblock 30 includes an elongated groove or bore 32 of circular crosssection for receiving the conduit 10 therein. The bore 32 extendscontinuously to flared end walls 34 which are disposed at apredetermined angle, such as 45°, from the axial extent of the bore 32.The conduit 10 is mounted in the holding block 30, with the unformedfirst end 14 disposed adjacent one end of the holding block 30 in theflared end wall portion 34. A mating holding block 30 is then secured tothe holding block 30 shown in FIG. 2 and a tool, such as a punch 36, isforcibly urged against the first end 14 of the conduit 10.

The punch 36 can be formed with a reverse angled face 40, spaced fromthe end of a pilot nose 38, which angled face 40 engages the end 14 ofthe conduit 10 and forces the end of the conduit 10 radially inward asshown in FIG. 3.

In FIG. 3, the same or a different pair of holding blocks 30 are used ina second step of the present method. After the end 14 of the conduit 10has been flared radially outward and the outer end portion thereof bentinwardly, as shown in FIG. 3, a different and unique tool 46 is employedto complete the flaring as well as to form the reduced resistance bead28 in the first end 14 of the conduit 30. As shown in FIG. 3, and ingreater detail in FIG. 4, the tool 46 is formed with a generallycylindrical shank 48. A conical surface formed of a first conicalsection 52 and a spaced, second conical section 54 are formed on one endof the shank 48 and extends axially therefrom. A piloting nose 50 havingan O.D. smaller than the I.D. of the conduit 10 is formed at the end ofthe first conical surface 52 and serves to center the tool 46 in theconduit 10.

A recess 56 is formed between the first and second conical surfaces 52and 54. The recess 56 forms the reduced resistance bead 28 in the innerflange 20 of the conduit 10 when the tool 46 is forcibly urged into theconduit 10 mounted in the pair of holding blocks 30. Thus, the recess56, although being illustrated as having a generally arcuate orspherical cross section, may be formed in any one of the above-describedshapes to provide the desired shaped reduced resistance bead 28.

In use, when the tool 46 is forcibly urged into the first end 14 of theconduit 10 mounted in the holding blocks 30, the first and secondconical surface portions 52 and 54 bend the partially folded over flange42 of the conduit 10 back on itself into registry with the outer flange16 of the conduit 10 until the outer flange 16 is disposed in registrywith the flared end walls 34 of the holding blocks 30. This forms theouter and inner flanges 16 and 20 at the desired flared angle, such as45°, as described above. At the same time, the forced engagement of thetool 46 with the conduit 10 extrudes a portion of the conduit metal inthe first end 14 of the conduit 10 from the inner flange 20 into therecess 56 in the tool 46 to form the reduced resistance bead 28 having ashape corresponding to the shape of the recess 56.

Besides using the tool 46 to extrude the bead 28 from the end of theconduit 10, the bead can also be formed by machining to the desiredshape.

Referring now to FIG. 5, there is depicted an exemplary application ofthe conduit 10 having a reduced resistance bead 28 formed thereonaccording to the method described above. In this application, theconduit 10 is connected in sealing engagement by a fitting 60 to areceiver means 62. The fitting 60 is in the form of a body 64 having aplurality of hex-shaped flats 66 formed exteriorly thereon. A bore 68extends through the body 64 and loosely receives the conduit 10therethrough, the I.D. of the bore 68 being slightly greater than theO.D. of the conduit 10. An end portion 70 of the body 64 of the fitting60 extends from the hex flats 66 and has external threads 72 formedthereon. An inner conical surface 74 is formed on the end portion 70adjacent the exterior end thereof. The conical surface 74 engages theconical surface 18 on the outer flange 16 of the conduit 10, as shown inFIG. 5.

The receiver means 62 may comprise any mounting member to which a fluidconduit 10 is mounted. Thus, the receiver means 62 may comprise a block,valve, etc. A seat 80 is formed within the receiver means 62 andsurrounds a through bore 82 which is alignable with the bore 13 in theconduit 10. The seat 80 has an annular, conical end face 84 whichmatingly engages the reduced resistance bead 28 and/or the inner conicalsurface 22 of the conduit 10. A plurality of threads 85 are formedinternally within an annular end of the receiver means 62 for matingengagement with the threads 72 of the fitting 60 to join the fitting 60to the receiver means 62 as well as to apply torque to forcibly engagethe first end 14 of the conduit 10 with the conical seat 84 in thereceiver means 62. Other means for clamping or joining the fitting 60 tothe receiver means 62 may also be employed.

In use, the axial extent of the conduit 10 is first slid into the bore68 in the fitting 60 prior to the fitting 60 being threadingly joined tothe receiver means 62. Torque applied to the fitting 60 by.means of atool engaged with the hex flats 66, forcibly urges the conical surface74 in the fitting 60 into engagement with the exterior conical surface18 on the first end 14 of the conduit 10 and forces the opposed innerconical surface 22 of the inner flange 20 of the conduit 10 intoengagement with the conical surface 84 of the seat 80 in the receivermeans 62.

Assuming that all of the components are manufactured within specifiedmanufacturing tolerances, such that the mating conical surfaces 74 andthe fittings 60, the exterior conical surface 18 and the inner conicalsurface 22 of the conduit 10 and the surface 84 of the seat 80 in thereceiver means 62 are concentric with each other, a predetermined amountof force applied to the fitting 60 will be sufficient to concentricallydispose the inner surface 22 of the first end 14 of the conduit 10 intometal-to-metal contact with the face 84 of the seat 80 in the receiver62 to form a leak-free seal therebetween.

However, it is more likely that one of the conical faces is eccentric,or varies angularly, or the conduit 10 is not co-axially aligned withthe seat 80 in the receiver 62. The reduced resistance bead 28 of thepresent invention overcomes any eccentricity or angular variances whichmay exist between the mating conical surfaces and functions in one oftwo different ways, depending upon which material forming the conicalseat 80 and the receiver 62 or the material forming the conduit 10 issoftest. In FIG. 5, it is assumed that the conical seat 80 in thereceiver 62 is softer than the material forming the conduit 10. Wheneccentricity or angular variances exist between the mating conicalsurfaces, torque applied to the fitting 60 will urge a predeterminedangular portion of the reduced resistance bead 28, as indicatedgenerally by reference number 90 in FIG. 5, into and deforming a portionof the conical seat 80 in the receiver 62. This deformation continuesuntil the remaining annular extent of the bead 28 sealingly engages theremainder of the conical surface 84 of the seat 80 to form a leak-freeseal therebetween. It should be noted that the arcuate shape of theexample of the bead 28 shown in FIG. 5 creates a longer leak path forincreased leak resistance as compared to the length of the inner conicalsurface 22 of the conduit 10.

If the conduit 10 is formed of a softer material than the seat 80 of thereceiver 62, a different deformation occurs if eccentricity or angularvariances exist between the mating surfaces, as shown in FIG. 6. In thisexample, when the fitting 60 forcibly urges the flared end 14 of theconduit 10 into engagement with the surface 84 of the conical seat 80, aportion of the reduced resistance bead 28, as shown by reference number94 in FIG. 6, will deform itself. Such deformation will occur over apredetermined angular extent of the bead 68 until the opposed portion ofthe bead 68, as shown by reference number 96, sealingly engages thesurface 84 of the seat 80 to form the desired leak-free seal between theconduit 10 and the seat 80 of the receiver means 62.

It should be noted that in both examples shown in FIGS. 5 and 6,regardless of which element undergoes deformation when the flared end 14of the conduit 10 is forcibly urged into sealing engagement with theseat 80 in the receiver means 62, the reduced resistance bead 28 has asmaller volume of material as compared to the larger volume of theentire inner flange 20 of the first end 14 of the conduit 10 so as tomore easily undergo deformation itself, as shown in FIG. 6, or to moreeasily cause deformation in the seat 80, as shown in FIG. 5. Thissubstantially reduces the amount of torque needed to be applied to thefitting 60 to forcibly urge the conduit 10 into complete leak-freesealing engagement with the seat 60 in the receiver means 82.

This increased leak resistance with the same or less amount of appliedtorque was established by tests run on a number of samples of aconventional double or inverted flared end conduit without the reducedresistance bead 28 of the present invention and samples of a conduit 10having the reduced resistance bead 28 constructed as shown in FIG. 1.The test samples without the reduced resistance bead required an averageof 11.17 newton meters of torque to achieve a leak-free seal between theconduit and the receiver seat. The samples of the conduit 10 utilizingthe reduced resistance bead 28 of the present invention required only anaverage of 6.83 newton meters to achieve the leak-free seal. Thisrepresents a reduction of approximately 39% in the amount of torquerequired to sufficiently tighten the fitting 60 to the receiver 62 toform a leak-free seal between the flared end 14 of the conduit 10 andthe seat 80. Even when statistical corrections are made to the testaverages to account for the sample size, a conduit 10 having the reducedresistance bead 28 of the present invention thereon still shows arequired torque force of approximately 31% less than that required forthe conventional conduits lacking the reduced resistance bead 28.

FIG. 7 depicts the use of a reduced resistance bead of the presentinvention on other shaped elements not having conical mounting surfaces.In FIG. 7, a first member 100 is provided with a first mounting face orsurface 102. A second member 104 provided with a corresponding mountingface or surface 106. As shown in FIG. 7, the mounting surfaces 102 and106 are arranged at a 90° angle with respect to the remaining portionsof each member 100 and 104.

A reduced resistance bead 108 is formed on one of the members, such asmember 104, and extends integrally outward from the mounting surface 106of the member 104. Suitable joining means, such as a fitting 110 whichthreadably engages a threaded bore in the first member 100, are employedto forcibly connect the first and second members 100 and 104 in matingengagement. The reduced resistance bead 108 functions in the same manneras the bead 28 described above and undergoes deformation or causesdeformation in the mounting face 102 of the member 100 to account forany eccentricity or angular variances between the two members 100 and104 and to provide a leak-free seal between the metal-to-metal engagedsurfaces 102 and 106 of the members 100 and 104.

FIGS. 9 and 10 depict the use of a reduced resistance seal or bead 12,identical to the bead 28 20 described above, on a single flared endconduit 114. In this application, the bead 112 is integrally formed onthe inner conical surface 116 of the single flared end flange 118 of theconduit 114. The bead 112 sealingly engages a conical mounting surface120 formed in a receiver 122 which is one part of a conventional twopiece tube assembly also including a fitting 124. The fitting 124 andreceiver 122 function in the same manner as the fitting 60 and receiver62 shown in FIG. 5 to sealingly mount the single flared end flange 118of the conduit 114 to the receiver 122.

Other fitting/receiver assemblies, such as a three piece assemblyemploying an additional sleeve or collar, may also be employed witheither of the conduits 10 and 112 having the reduced resistance seals orbeads of the present invention formed thereon.

In summary, there has been disclosed a unique mounting arrangement andmethod for forming a leak-free seal between the mating mounting faces oftwo members arranged in metal-to-metal contact. A reduced resistanceseal or bead is integrally formed on the mounting surface of one memberand undergoes deformation or causes deformation in the opposite mountingsurface to account for any eccentricity, angular variance, ormisalignment of the two members when the two members are urged intoforced engagement. The reduced resistance bead of the present inventionis easily formed on any component utilizing existing assembly methodssuch that it is usable as a drop-in replacement for existing components,such as fluid components, without requiring any modifications to thecorresponding fittings, receivers or other mounting or connectorelements. The unique reduced resistance bead also requires the same orless torque to join the fittings together to form the desired leak-freeseal.

What is claimed is:
 1. A method of forming a flared end on a fluidconduit comprising the steps of: flaring a first end of a conduitradially outward from an axial extent of the conduit by axially pressinga tool into the first end of the conduit to form exterior and interiorparallel conical surfaces on the first end of the conduit, both disposedat a predetermined angle from the axial extent of the conduit; andsimultaneously with the flaring of the first end of the conduit,extruding an annular reduced resistance bead having a sidewallterminating in an outer end by the axial pressing of the tool as acontinuous, one-piece, radially inward projecting extension from a planedefined by the interior conical surface.
 2. The method of claim 1wherein the step of forming the reduced resistance seal comprises thestep of forming a reduced resistance bead having an arcuate shapedexterior surface.
 3. The method of claim 1 wherein the step of formingthe reduced resistance bead comprises the step of forming a reducedresistance bead having a polygonal shaped exterior surface.
 4. Themethod of claim 1 wherein the step of flaring the first end furthercomprises the step of: bending a portion of the flared first end of theconduit inward on itself to form outer and inner substantially parallelflanges, the exterior conical surface formed on the outer flange and theinner conical surface formed on the inner flange.
 5. A method ofsealingly joining two members together comprising the steps of: forminga first mounting surface on a first member: forming a second mountingsurface on a second member by axially pressing a tool into the secondmember to form exterior and interior parallel conical surfaces extendingangularly from the axial extent of the second member; simultaneouslywith the step of forming the second mounting surface, extruding anannular reduced resistance bead by the axial pressing of the tool as acontinuous, one-piece extension from a plane defined by the secondmounting surface of the second member; and joining the first and secondmembers to bring the reduced resistance bead into complete annular,sealing engagement with the first mounting surface of the first member.6. The method of claim 5 wherein the step of forming the first mountingsurface further comprises the step of forming a first conical mountingsurface; and wherein the step of forming the second mounting surfacefurther comprises the step of forming a second conical mounting surface.7. The method of claim 6 further comprising the steps of: forming thesecond member as a hollow conduit; providing a die having a conicalsurface; providing the tool with a conical exterior surface and anannular recess formed between opposed axial ends of the conical surface;and wherein the steps of forming a second mounting surface andsimultaneously forming a reduced resistance bead includes the step offorcibly urging the tool into an end of the second member disposed inthe die such that the conical surface on the tool flares the end of thesecond member radially outward at a predetermined angle from the axialextent of the second member into contact with the conical surface of thedie and simultaneously extrudes the reduced resistance bead in theflared end of the second member.
 8. The method of claim 5 furthercomprising the steps of: providing a fitting having a third mountingsurface formed thereon; forcibly joining the fitting to the secondmember while bringing the third mounting surface of the fitting intoengagement with the second member and forcibly urging the secondmounting surface of the second member into sealing contact with thefirst mounting surface of the first member.
 9. The method of claim 8further comprising: during the step of joining the first and secondmembers together, deforming the reduced resistance seal to an extentnecessary to bring the entire annular extent of the reduced resistanceseal into sealing engagement with the first mounting surface.
 10. Amethod of forming a flared end on a fluid conduit comprising the stepsof: forming a first end of a conduit radially outward from an axialextent of the conduit with an end extending radially inward by axiallypressing a first tool into the first end of the conduit; bending aportion of the first end of the conduit inward on itself by axiallypressing a second tool into the first end of the conduit to formexterior and inner substantially parallel flanges, an exterior conicalsurface formed on the outer flange and an inner conical surface formedon the inner flange; and simultaneously with the bending of the flaredfirst end of the conduit extruding an annular reduced resistance beadhaving a sidewall terminating in an outer end by the axial pressing ofthe second tool as a continuous, one-piece, radially inward projectingextension from a plane defined by the interior conical surface.
 11. Themethod of forming a flared end on a fluid conduit comprising the stepsof: flaring a first end of a conduit radially outward from an axialextent of the conduit by axially pressing a tool into the first end ofthe conduit to form exterior and interior parallel conical surfaces onthe first end of the conduit, both disposed at a predetermined anglefrom the axial extent of the conduit; the step of flaring the first endfurther including bending a portion of the flared first end of theconduit inward on itself to form outer and inner substantially parallelflanges, the exterior conical surface formed on the outer flange and theinner conical surface formed on the inner flange; and simultaneouslywith the flaring of the first end of the conduit, extruding an annularreduced resistance bead having a sidewall terminating in an outer end,the bead formed as a continuous, one-piece, radially inward projectingextension from a plane defined by the interior conical surface.
 12. Amethod of forming a flared end on a fluid conduit comprising the stepsof: forming a first end of a conduit radially outward from an axialextent of the conduit with an end extending radially inward; bending aportion of the first end of the conduit inward on itself to formexterior and inner substantially parallel flanges, an exterior conicalsurface formed on the outer flange and an inner conical surface formedon the inner flange; and simultaneously with the bending of the flaredfirst end of the conduit, extruding an annular reduced resistance beadhaving a sidewall terminating in an outer end, the bead formed as acontinuous, one-piece, radially inward projecting extension from a planedefined by the interior conical surface.